Landscapes of extinction and evolution: Earth surface processes in the late Palaeozoic

生命在行星表面长期形成过程中的作用需要被理解，以确定地球在已知的岩石行星中是否独一无二，并对生物圈未来的变化进行预测：沉积岩记录是一个有价值的档案，揭示了地球表面的过程是如何与生物一起进化的，而晚古生代的动荡期是一个理想的案例研究来询问这个问题。沉积和地貌过程与地球上的大多数生命发生在同一个舞台上，物理过程和形式的生物塑造在当今是重要的。不同的生物聚集或分解沉积物；侵蚀、混合、捆绑或稳定沉积物桩；并且可以引起湍流，集中或抑制运输沉积物的流体的运动。通过物理-生物反馈，这些过程塑造了我们今天所知道的地球，决定了沉积物类型和沙丘和河道等地貌的形态。如果我们要充分了解这些过程的重要性，我们需要集中研究它们最初发挥作用的地质间隔。晚古生代是研究这些过程如何创造地球地貌的最佳时期。这一间隔时间晚于许多陆地景观工程（如树木、穴居生物）的进化，但受到地球系统重大剧变的影响：赤道干旱化和石炭纪末期热带雨林的崩溃、主要的冰河期和地球历史上最大规模的物种灭绝。古代景观的演变被记录在沉积记录中，作为单个演替体的相和岩性属性来识别过去的环境。从地球系统中90 Ma的大湍流间隔中对这些环境的整体看法，将展示当不同的生物群体受到全球变化的压力或有利时，对景观和沉积的反馈。该项目将重点研究晚石炭世（约310 Ma）至中三叠世（约290 Ma）这段时间。这段时间见证了物种灭绝和栖息地破坏的主要事件（如卡西莫瓦热带雨林崩溃、P-T大灭绝）和气候变化（如LP冰河期、欧美二叠纪沙漠化、卡尼期洪积期）。该项目将评估景观和沉积如何响应并记录这些系统变化。学生将遵循一系列先前已被证明在评估与生命进化相关的全球变化（即陆地植物进化对河流形式的影响，以及动物入侵土地的后果）方面取得成功的工作包。该项目将从英国和世界范围内确定一套合适的案例研究，其中详细的沉积地质模型将从原始的野外数据中构建，以确定在类似的构造和气候环境中，从重大事件前后的间隔中确定景观。这将与建立一个主要数据库相结合，该数据库将从划定的晚古生代区间确定非海相的长期特征。这种结合了详细的沉积地质学实地考察案例研究和随时间变化的沉积特征地图集的方法，将坚定地解决地球景观是如何应对地球前现代历史上最动荡的时期之一的问题。

The role of life in the long-term shaping of the planetary surface needs to be understood to ascertain whether Earth is singular among known rocky planets, and to frame predictions of future changes to the biosphere: the sedimentary rock record is a valuable archive that reveals how Earth surface processes evolved in line with organisms, and the turbulent interval of the late Palaeozoic is an ideal case study to interrogate this question.Sedimentary and geomorphic processes occur in the same theatre as the majority of life on Earth, and biological shaping of physical processes and form is important at the present day. Different organisms aggregate or disaggregate sediment; erode, mix, bind, or stabilize sediment piles; and can induce turbulence in, concentrate, or dampen the movement of fluids that transport sediment. Through physical-biological feedback, these processes shape the Earth as we know it today, determinign sediment type and the morphology of landforms such as dunes and river channels. If we are to fully understand how significant these processes are, we need focussed investigation of geological intervals when they first came into play. The late Palaeozoic is a perfect interval to study how these processes have created the landscapes of planet Earth. The interval post-dates the evolution of many agents of terrestrial landscape engineering (e.g., trees, burrowing organisms), but was affected by major upheavals in the Earth system: equatorial aridification and the collapse of the rainforests at the end of the Carboniferous, a major ice age, and the biggest mass extinction in Earth history.Ancient landscape evolution is archived in the sedimentary record, as individual successions host facies and lithological attributes that identify past environments. A holistic view of these environments, from a 90 Ma interval of major turbulence in the Earth system, will demonstrate the feedback on landscapes and sedimentation that are imparted when different groups of organisms are stressed or advantaged by global changes. The project will focus on the interval of the late Carboniferous (c. 310 Ma) through to the mid Triassic (c. 290 Ma). This interval witnessed major episodes of extinction and habitat destruction (e.g., Kasimovian rainforest collapse; the P-T mass extinction), and climate change (e.g., LP ice age; Permian desertification in Euramerica; the Carnian pluvial episode). The project will evaluate how landscapes and sedimentation responded and recorded these system shiftsThe student will follow a series of work packages that have previously been shown to be successful in assessing global changes related to life evolution (namely, the impact of land plant evolution on fluvial form, and the consequences of the invasion of the land by animals). The project will identify a suite of suitable case studies, from the UK and worldwide, where detailed sedimentary geological models will be constructed from original field data, to ascertain landscapes in similar tectonic and climatic settings, from intervals before and after major events. This will be coupled with the construction of a major database, which will identify secular characteristics of non-marine facies from delineated intervals within the late Palaeozoic. This combined approach of detailed sedimentary geology fieldwork case studies, and an atlas of evolving seidment character through time, will firmly address how the Earth's landscapes responded to what was one of the most turbulent periods of the planet's pre-modern history.